Especially in automotive engineering, and here in particular in the field of passenger compartment coverings or steering wheels, there are frequently used components which have both portions made of a foamed or injection-molded plastic material and electric or electronic components with the associated cables and plugs. The electric lines can subsequently be mounted in the finished foamed component, if guiding passages have been left by the foaming tool. However, this method often involves much work, as after the foaming process another working step must be performed. In certain cases, for instance when using foam-coated switches or heating mats for a steering wheel heating, the electric leads must also be foam-coated at least in part. In this case, the electric connecting lines have so far either protruded from the foaming mold (when closing the mold, care must be taken to avoid a damage of the cable or the plug housing) or they are foam-coated as well, where after the foaming process a plug must be liberated from foam and be cleaned with much effort. Therefore, to shorten the required working time and to avoid damages of the components during manufacture, there is a need of a simple method of foam-embedding cables.